MITOCHONDRIAL DEFECTS IN NEURO-OPHTHALMOLOGICAL DISEASE

神经眼科疾病中的线粒体缺陷

• 批准号: 2163769
• 负责人: MICHAEL P KING
• 金额: $ 29.14万
• 依托单位: COLUMBIA UNIV NEW YORK MORNINGSIDE
• 依托单位国家: 美国
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-04-01 至 1996-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2163769
• 关键词: ataxia; cell growth regulation; cellular respiration; central nervous system disorders; congenital eye disorder; disease /disorder model; extrachromosomal DNA; human tissue; hydrogen transporting ATP synthase; inborn metabolism disorder; lactic acidosis; membrane potentials; mitochondrial DNA; mitochondrial membrane; molecular pathology; nucleic acid hybridization; nucleic acid sequence; phenotype; point mutation; retinitis pigmentosa; tissue /cell culture

The mitochondrial encephalomyopathies are a clinically, morphologically, and biochemically diverse group of disorders. In the past several years, specific mitochondrial DNA (mtDNA) mutations have been found to result in several such human diseases. Unfortunately, there has been little or no correlation between the identification of the mtDNA mutations, the presumed etiology, and the pathogenesis of these disorders. The goal of this proposal is to analyze the pathological consequences and the molecular genetic causes of several specific mtDNA mutations causing neuro-ophthalmological disease. This analysis will take advantage of a unique cell culture system that permits the analysis of mtDNA mutations in a neutral nuclear background. This system is based upon the isolation of human cell lines that completely lack mtDNA (p-O cell lines) and the ability to repopulate these cells with exogenous mitochondria, and thus, mtDNA. This system will be applied to the analysis of the disease MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes). Two point mutations, both in tRNA-Leu(UUR) of the mtDNA, are known to result in this disease. By examining the biochemical, morphological and genetic consequences of these two mutations, and comparing the results, it should be possible to determine the precise molecular mechanism of pathogenesis. In a similar fashion, NARP (neurogenic muscle weakness, ataxia and retinitis pigmentosa), caused by a point mutation in the mtDNA-encoded subunit 6 of ATP synthetase, and other neuroophthalmological diseases will be studied. Only after specific defects and their causes are known, will it be possible to develop rational therapies for patients suffering from these diseases. This in vitro system will permit the exact metabolic requirements for cells with impaired respiratory chain function to be determined. In addition, the effects of different growth conditions or treatments on the mutated and wild-type mtDNAs can be examined. If one genome can be preferentially damaged or inhibited in its replication, it may be possible to devise treatments for these currently incurable, and often fatal diseases. In addition to those diseases, being studied in this proposal, this model system can also be applied to the study of other diseases where mitochondrial involvement is known or suspected, and the proposed analyses will provide a foundation for these future characterizations.

线粒体脑病在临床上，形态学上是一种 以及生化多样的疾病。 在过去的几年中， 已经发现特定的线粒体DNA（mtDNA）突变导致 几种这样的人类疾病。 不幸的是，几乎没有或没有 mtDNA突变的鉴定， 假定的病因和这些疾病的发病机理。 该提案的目的是分析病理后果和 几种特定mtDNA突变的分子遗传原因导致 神经嗜罗性疾病。 该分析将利用 允许分析mtDNA突变的独特细胞培养系统 在中立的核背景中。 该系统基于隔离 完全缺乏mtDNA（P-O细胞系）的人类细胞系和 能够用外源线粒体重新填充这些细胞，从而 mtDNA。 该系统将应用于疾病Melas的分析 （线粒体肌病，脑病，乳酸性酸中毒和中风样 情节）。 在mtDNA的tRNA-leu（Uur）中，两个点突变均为 已知会导致这种疾病。 通过检查生化， 这两个突变的形态和遗传后果，以及 比较结果，应该可以确定精确 发病机理的分子机制。 以类似的方式，narp （神经源性肌肉无力，共济失调和色素性视网膜炎），由 ATP合成酶的mtDNA编码的亚基6中的点突变，和 还将研究其他神经嗜血率疾病。 只有之后 特定缺陷及其原因是已知的，是否有可能 为患有这些疾病的患者开发理性疗法。 该体外系统将允许确切的代谢要求 要确定呼吸链功能受损的细胞。 另外，不同生长条件或治疗对 可以检查突变和野生型mtDNA。 如果一个基因组可以 优先损坏或抑制其复制，可能是 可能为这些目前无法治愈的治疗设计，并且经常 致命疾病。 除了这些疾病之外，还在研究 提案，此模型系统也可以应用于其他 已知或怀疑线粒体参与的疾病， 拟议的分析将为这些未来提供基础 特征。